7 Words in my understand that help me cognitively internalize God as Trinity:
Mystery: He is a Being beyond comprehensive understanding.
Uncreated: God exists continually outside the created order; self-existent.
Three: God is three persons or three with own identifying personhoods.
Same: God is same in essence, substance, character, nature and manifested in glory.
Complete: God is in every way perfect and relates out of love not need.
Fellowship: Conditionally-oriented bond based in unchanging-faithful interdependent love.